Radio reception apparatus



March 29, 1932. o. 'r. M ILVAINE RADIO RECEPTION APPARATUS Sheets-SheetFiled Oct. 7, 192'! Oran T. A2 Iloaine Attornegs March 29, 1932. o,MOILVAINE RADIO RECEPTION APPARATUS 2 Sheets-Sheet Filed Oct. 7, 1927Oran 'T: M Ilva-l-ne I Inventor Attornegs or on a conducting layerPatented Mar. 29, 1932 v UNITED STATES PATENT OFFICE ORAN '1. KCILVAINE,01' EAST GLEVELND, OHIO, ASSTGNOR T0 MGIL'VAINE PATENT conrom'rron,

OF ST. CHARLES, ILLINOIS, L. (K'IB-POIBA'JPION OF DELAWARE RADIORECEPTION APPABA T'FS Application filed October 7, 1927. Serial No.224,608.

This invention relates to radio apparatus and has for its object theprovision of new, 1mproved, and simplified apparatus for the receptionof radio signals; the provision-of radio reception apparatus which shallbe operative without external current or potential supply; the provisionof a tube type of radio reception apparatus which shall be adapted todetect and amplify signals merely under the influence of-heat; whilefurther objects and advantages of the invention will become apparent asthe description proceeds.

In the drawings I have shown certain physical embodiments of myinvention, although it will be understood that the same are intended tobe merely illustrative and not limiting. Fig. 1 is a vertical sectionalview of an apparatus containing my improvement; Fig. 2 is a horizontalsectional view of the same corresponding to the line 2-2 of Fig. 1; Fig.3 is a perspective view partly in section 0 a modified form ofapparatus; Fig. i is a sec tional view through one of the tubes showingthe essential structure both of the detector, the amplifier, and thepotential tuber Fig. 5 is a diagram of the connections of the deviceshown in Fig. 1; and Fig. 6 is a diagram of the connections of thedevice shown in Fig. 3. The apparatus herein described depends upon theuse of tubes of the general type set forth in my application SeriaLNo.209,281, filed July 29, ode consists of a layer of some substance whichreadily emits electrons under the influence of radiant energy thismaterial being plated directly on the glass wall of the tube which isitself suitthe tube wall; the anode is also, preferably, formed of athin layer of conductive material plated on glass; and the tube ispreferably made of a new and peculiar shape which is specially adaptedto the mode of potential production herein described.

In its preferred form the tube comprises a globe of glass as shown inFig. 4 with a cylindrical side wall 1 reduced at one end to theexhausting stem which is ultimately sealed ofi leaving a point 2.Hermetically fastened to the oppositeend of the side wall is the flange4 of the flare which has a cylindrical ably plated upon f as indicatedat the portion 46 of the 1927. In these tubes the cathzirconium,

walled'hollow body 5 projecting into the globe and spaced from andconcentric with the outer wall and extending nearly to the closed endthereof. The flange is sealed to the outer wall at in the usual mannercustom ary in making incandescent lamps, and the two parts thusassembled define a chamber which is everywhere annular except near thepoint 2. In the preferre form of my invention the inner surface of thewall 1 is rendered conducting by the deposit thereon of a layer 9 of asuitable substance, while the adjacent surface of the body 5 is likewiseprovided with the layer 8 of suitable conduct ing substance. Theselayers may consist of the same or difi'erent substances, and may both beelectronically emissive. or only one of the same may be emissive undergiven conditions. It is necessary that some discontinuity be providedbetween the two surfaces globe. In the case of a tube used merely forthe production of potential no'intermediate element or grid is employed.but in case of a tube employed for detecting or amplifying signals agrid element 10 is interposed between the layers 8 and 9 but out ofcontact with both of the same. The three elements are connected toterminal wires which lead downwardly through the seal 45.

For a set of shown it is considered preferable to employ tubes whereinthe outer layer 9 constitutes the cathode and the innerlayer 8 theanode. It is possible to make both these layers of the sameelectronically emissive metal and maintain a sufiicient temperaturediiferent 'between the two to insure an adequate potential generation;it is preferable, however, in most cases, to employ different substancesfor the two walls which shall diifer in their electronic emissivity tureso as to produce the desired operation. The emitting material mayconsist of any suitable substance for that purpose, for example silver,thorium, potassium, sodium, caesium or any of the alkali earth metals;the anode may consist of any of these, or in addition any otherconductive substance either plated upon the body 5 or otherwise even atthe same tempera-.

supported in facial relation with the layer 9, so that when the latteris sufiiciently heated a part of the electrons expelled therefrom shallbe able to cross the gap and electrify the layer 8, whereupon thelatter, either by being of a less emissive metal or by being maintainedat a lower temperature, can become relieved bf its charge only bycurrent flow through an external circuit.

As a convenient and very simple mode of utilizing these tubes in theformof a radio set, I have illustrated in Figs. 1 and 2 a rectangularmetal box comprising top 11, sides 12-12 and ends 13, 13 flanged at 14for application to a horizontal bottom plate 15 in such wise that oneend shall project therebeyond. Supporting this bottom plate is a block16 formed with a plurality of vertical recesses 17 provided with sockets18 adapted to receive the bases 19 with which the tubes are provided.The bottom plate 15 is formed with apertures 2020 registering with therecess 17 to permit the'tubes to rise into the body of the box. Theoverhanging end of the box is formed with an aperture 21 adapted toreceive the chimney 22 of a kerosene lamp or other suitable heat source.The opposite end is here shown as provided with a chimney 23 and damper24.

In case it be desired to maintain a temperature difference between theinterior and exterior of the tubes, such an expedient can be employed asis illustrated in Fig. l, wherein a rod 26 of copper or other heatconductive metal is located inside each of the bodies 5, 5, its outerend being connected to a heat dissipating plate 27. Many otherexpedients can be used.

Each of the tubes heretofore described as employed in this set isprovided with three elements, the cathode 9, anode 8 and grid 10heretofore described. With these can also be used some plain potentialtubes, if desired for the purpose of increasing the power of the set,said tubes being here indicated at 28 and made of smaller size than thefirst described tubes and supported in the top 10 with their exteriorsurfaces receiving the maximum heat while their interiors are cooled byexternal convection. Any desired system of connections can be employed,the diagram in Fig. 5 being merely one of many circuits which can beemployed.

3O denotes an aerial or antenna inductively coupled at 31 through avariable condenser 32 with a tube A of the type herein described. Thistube is here shown as coupled to form a radio frequency amplifier, andits anode 8 is connected-through an inductive coupler 33 and variablecondenser 34 to a second tube B also serving as a radio amplifier,having its anode 8 connected via inductive coupler 35 and variablecondenser 36 to a third tube 0 here arranged as a detector. The anode 8of tube C is connected through an inductive coupler 37 with a fourthtube D here arranged as an audio f equency amplifier. The anode 8 oftube D is connected through the inductive coupler 38 with a further tubeE, also acting as an audio frequency amplifier. The anode 8 of tube E isconnected to the sound producer 40.

As a B battery I have shown a series F F of the thermo-cellshereinbefore described, connected together in series. The negative lead41 is connected to the cathode 9 of tubes A, C, D, and E; the positiveterminal 42 is connected to the sound producer 40. Intermediate taps 4.3and 44 can be connected to the circuit at different points in anydesired manner. I have shown for illustrative purposes a compositecircuit which is obviously capable of many modifications, althoughitself very successful.

many cases it is sufficient to use the three element tubes withoutpotential devices of any kind, in which case the parts can still furtherbe simplified as illustrated for example in Fig. 3, wherein 50 denotes arectangular metal box provided with a plurality of tubes of the typeillustrated in Fig. 4 hereof, all connected together according to somesuitable system as for example the circuit illustrated in Fig. 6, andadapted to operate merely by being subjected to action of a suitableheat source. Inasmuch as each tube is itself a source of potential, anexternal current can be produced and governed without external aid,suflicient for many purposes but obviously not so strong as oneexternally supplemented. Inasmuch as the reference characters of Fig. 6are the same as employed in Fig. 5 it is not believed necessarry torepeat the description of the circuit. Of course it will be understoodthat the electrical and magnetic couplings and the sound producer mustbe designed with reference to the usein question, namely a comparativelysmall potential and low resistance.

The apparatus can with small modifications be adapted for use with acoal stove, wood fire, steam radiator, or even intense sunlight, andbecause of the many changes in detail which are possible I do not limitmyself in any wise except as recited in the annexed claims.

Having claim is: p v

1. Radio reception apparatus comprising, in combination, a plurality ofevacuated tubes each having an anode and cathode, said cathode being ofa material which will produce a potential between said anode and cathodeby electronic expulsion when said cathode is subjected to a source ofheat, a source of heat external to said tubes, control electrodes in.certain at least of said tubes, and connections between the variouselectrodes of said tubes, said connections including capacities, inductances and terminals provisions.

thus described my invention what 2. Radio reception apparatuscomprising, in combination, a pluraht of evacuated tubes each having ananode an cathode, said cathode being of a material which will produce apotential between said anode and cathode by electronic expulsion whensaid cathode is subjected to a source of heat, a source of heat externalto said tubes, control electrodes in certain of said tubes, theremaining tubes being devoid of control electrodes, connections betweenthe tubes which contain control electrodes for the detection andamplification of radio signals, and connections between those tubeswhich do not contain control electrodes and the remaining tubes for theproduction of potential.

3. Radio reception apparatus comprising, in combination, a plurallty ofevacuated tubes each having an anode and cathode, said cathode being ofa material which will produce a potential between said anode and cathodeby electronic expulsion when said cathode is subjected to a source ofheat, a source of heat externalto said tubes, and circuit connectionsbetween the elements of said tubes.

4. Radio reception apparatus comprising, in combination, a plurality ofevacuated tubes each having an anode and cathode adapted to produce apotential by electronic expulsion when subjected to a source of heat, ametallic box having apertures in its walls, means for supporting saidtubes with their cathode containing parts inside the box and their anodecontaining parts in communication with the exterior of the box, andmeans for supplying heat to the interior of said box.

5. Radio reception apparatus comprising,

- in combination, a plurality of evacuated tubes,

' communication, one with the each comprising concentric glass wallsdefining an annular chamber having theanode and cathode plated onopposed inner surfaces, a metallic box having apertures in its wall,

and means for supporting said tubes in saidapertures with their innerand outer walls in interior and the other with the exterior of the box.

6. Radio reception apparatus comprising,-

in combination, a plurality of evacuated tubes, each comprisingconcentric glass walls defining an annular chamber having the anode andcathode plated on opposed inner surfaces, a metallic box havingapertures in its wall, means for heating the air inside said box, andmeans for supporting said tubes in said apertures with theircathode-carrying walls in contact with the internal atmosphere and theiranode-carrying walls opening outward- 1y to the outer atmosphere, thecathode comprising material which emits electrons when heated.

7. Radio reception apparatus comprising, in comblnatlon, a plurality ofevacuated tubes, each comprising concentnc glass walls defining anannular chamber having the an ode and cathode plated on opposed innersur faces, a metallicbox having apertures in wall, means for heating theair inside said box, and means for s porting said tubes in saidapertures with t eir' cathode-carrying walls in contact withthe-internal atmosphere and their anode-carrying walls opening outwardlyto the outer atmosphere, the cathode comprising material which emitselectrons when heated, and means for abstracting heat from theanode-carrying walls.

8. Radio reception apparatus comprising a supporting device, andelectron tubes mounted therein having anodes and cathodes, each cathodecoated with a substance which is adapted to emit electrons when heatedand each anode facing the corresponding cathode at a short distance, andmeans tor a%ply1ng external heat to said tubes.

9. adio reception apparatus comprising a support having sockets, aplurality of electron tubes carried by said sockets, said tubes havingcathodes adapted to emit electrons when heated, anodes and controlelectrodes also located in said tubes, a box adapted to receive thecathode-containing part of said iubes, and means for heating thefluid'in said 10. Radio reception apparatus comprising a plurality ofelectronic tubes each containmg anode, cathode, and control electrode,

and other electronic tubes each containing an tubes each having an anodeand cathode adapted to produce a potential by electronic expulsion whensubjected to a source of heat, a box having apertures in its walls,means for supporting said tubes with their anodeand cathode-containingparts in communication, one with the interior and the other with theexterior of the box, and means for producing a difference of temperatureinside and outside said box.

12. Radio reception apparatus comprising, in combination, a plurality ofevacuated tubes each having an anode and cathode adapted to produce apotential by electronic expulsion when subjected to a source oi heat, asupport for said tubes, means for heating the oathode-containing partsofsaid tubes, and means for shielding against heating theanode-consignature.

faces, and a metallic member having projectiogs adapted to enter theinner walls of said tu s.

14. Radio reception apparatus comprising, in combination, a plurality ofevacuated tubes, each comprising concentric glass walls defining anannular chamber having the anode and cathode plated on opposed innersurfaces, a box having apertures in its walls, means for supporting saidtubes with their inner walls presented to said apertures, and a metallicconducting member in each inner wall and projecting outside said box.

In testimony whereof I hereunto aflix my ORAN T. McILVAINE.

